Lighting systems for automotive vehicles may include lighting and signaling devices mounted or integrated to the front, sides and/or rear of the vehicles. These systems typically are designed to provide illumination for drivers to operate the vehicles after dark and to increase the visibility of the vehicles.
Vehicle lighting systems may include fog lamps. Fog lamps may provide a wide beam of light with a sharp cutoff at the top, and are generally aimed and mounted low. The fog lamps are intended to increase the illumination directed towards the road surface in conditions of poor visibility such as rain, fog or snow. Fog lamps may be used in place of dipped-beam headlamps for reducing the glareback from fog or snow.
While traditional automotive fog lamps use tungsten-halogen filament light sources, light emitting diodes (LEDs) have become frequently used in automotive lamps such as fog lamps. LED fog lamps may offer longer service life and better vibration resistance than traditional automotive fog lamps. However, challenges exist in the use of LEDs in automotive lighting devices due to the relatively low flux output of the LEDs. Moreover, even though high power LEDs may output around 80 to 100 lumens, the output flux may be unstable and may decline rapidly, unless good thermal management of the LED can be maintained.
It is therefore desirable to develop LED fog lamps with an enhanced flux output and efficiency. It is also desirable to develop automotive lighting systems that may provide improved durability, reliability, power consumption efficiency, size efficiency, natural coloring scheme, and design flexibility.